This week, BPR gardening expert Alison Arnold talks about how to do composting with earthworms.
Jeremy Loeb: As we enter the growing season it seems like a good time to start composting.. what would you recommend for people who might not have a lot of space to build a typical compost bin?
Alison Arnold: Worms…. Composting with worms or what is also called vermicomposting is a great alternative to the larger bin type of compost method. There are a lot of pluses to composting with worms….It's great if you don't have a lot of space (like apartment dwellers) or might be dealing with bears, it doesn't involve much work, it can be done year around, indoors or outdoors, kids love it AND the worm castings that result from their hard work is a great soil amendment.
JL: What do you need to get started?
AA: A container, some bedding, the worms and worm food like vegetable scraps and any compostable items from the kitchen.
JL: So tell us about the container and bedding – what’s involved there?
AA: Often called a Worm Bin, this is usually a wood or plastic container either purchased or made at home. It should be opaque and keep out light, have a tight fitting lid, and be at least 8-14 inches deep. Air holes re needed and so plan on dedicating this container just for the worms. The bedding can be shredded non-glossy newspaper, office paper or cardboard, or a mixture of paper, brown leaves, finished compost, or straw.
JL: OK so now what about the worms… when you say worms.. do you mean regular earthworms?
AA: Actually no.. the best worms for composting are the red wrigglers. They are the workhorses of worms for worm composting. It's recommended to start with at least one pound (about 1,000) red wigglers to one square foot of surface area of the worm bin to have a chance of developing a sustainable system and to purchase them from a worm grower to ensure you have the right kind.
JL: So the food then. Is it the same or different than what you would add to a normal compost bin?
AA: It’s very similar actually – things like vegetables scraps, coffee grounds and filters, tea bags, non-citrus fruit scraps and peels, moistened bread and shredded napkins make great food for worms. You definitely want to avoid meat, fish, dairy products, citrus, greasy foods, bones, twigs and branches or pet waste. Also odorous food like onions should be avoided because it can make the worm bin smell bad.
JL: So you put all of this together and then what?
AA: Well actually it might be a good idea to think about the location before you pull it all together. It can go indoors or outdoors but should be in a location where you will remember to use it and tend it on a regular basis. If you go indoors it can make a great conversation piece but be sure to provide a tray or something under the bin to protect the flooring. If you go outdoors make sure there’s shade during the summer months and a little insulation with blankets or straw during colder months. Worms are happiest or most active between 60 and 75 degrees F, although they will survive between 32 and 95 degrees with protection from the heat and cold.
Cooperative Extension has good information about worm composting – it’s good to read up and prepare well for the sake of you and your worms!